UNIVERSITY    OF    CALIFORNIA     AGRICULTURAL    EXPERIMENT   STATION 
COLLEGE   OF  AGRICULTURE  BENJ-  IDE  WHEEL".  P»»«»«T 

THOMAS    FORSYTH    HUNT,    Dean  and  Di r ector 

BERKELEY  h.  e.  van  norman,  vice-director  and  dean 

University  Farm  School 


CIRCULAR  No.  176 
October,  1917 


HOG  CHOLERA  PREVENTION  AND  THE 
SERUM  TREATMENT 

By  P.   T.  PETEKSEN 


CONTENTS 

PAGE 

How  Hog  Cholera  is   spread   1 

How  the  disease  reaches  herds 2 

General  preventive  measures 3 

Control  of  outbreaks  of  Hog  Cholera  by  disinfection 4 

Prevention  by  means  of  anti-hog  cholera  serum 6 

Adding  new  hogs  to  infected  premises 6 

Methods  of  using  anti-hog  cholera  serum • 7 

Advice  concerning  vaccination 7 

Equipment   necessary   to   vaccinate 9 

How  to   vaccinate 10 

How  to  obtain  serum  and  virus 14 


Hog  cholera  is  the  most  widespread  of  the  acute  infectious  diseases 
of  domestic  animals.  It  occurs  in  nearly  all  sections  of  California 
where  hogs  are  raised.  Some  localities  removed  from  shipping  routes 
are  free  from  the  disease,  but  there  are  also  remote  sections  where 
cholera  is  present.  The  cause  of  the  disease  is  an  organism  so  small 
that  it  will  pass  through  bacteria-proof  niters,  and  it  has  therefore 
been  named  "The  Filterable  Virus  of  Hog  Cholera."  The  disease 
is  contagious  only  to  swine  and  enters  the  body  usually  through  the 
digestive  tract.  An  incubation  period  of  seven  to  ten  days  elapses 
after  the  virus  is  ingested  before  symptoms  develop.  Hog  cholera 
should  be  suspected  in  any  herd  where  some  of  the  hogs  lie  in  the 


dark  corners,  refusing  to  come  out  and  feed,  and,  when  forced  out, 
arch  their  backs,  have  chills,  high  fever  and  coughs.  A  positive 
diagnosis  of  cholera  is  made  by  examining,  for  bright  red  spots,  the 
kidneys,  lungs,  intestines  and  inner  lining  of  the  bladder  of  a  recently 
killed,  sick  hog. 

The  only  protective  treatment  that  will  give  satisfactory  results, 
if  the  herd  is  infected,  is  anti-hog-cholera  serum.  Where  the  serum 
treatment  is  not  given,  all  the  hogs  on  the  premises  may  die,  the 
mortality  from  cholera  being  85  to  100  per  cent.  Prompt  use  of 
the  serum  in  an  infected  herd  will  save  most  and  possibly  all  the 
herd.  As  a  preventive  treatment  in  sound  herds,  serum  will  protect 
every  hog  against  cholera. 

HOW  HOG  CHOLERA  REACHES  HERDS  AND  IS  SPREAD 

Outbreaks  of  hog  cholera  may  start  directly  by  contact  between 
sick  and  well  hogs,  or  indirectly  by  contact  with  infected  material. 
The  sick  hog  is  the  most  important  factor  in  the  spread  of  cholera. 
All  the  -  body  tissues  and  the  discharges  that  pass  away  from  the 
cholera  hog  contain  the  virus.  The  premises  where  this  animal  is 
kept  and  the  cars  or  wagons  in  which  it  is  transported  become  readily 
contaminated  by  the  discharges.  Even  before  sickness  is  apparent 
the  hog  may  be  infect ed*and  is  a  dangerous  source  of  disseminating 
the  disease.  Experiments  have  proved  that  direct  contact  with  sick 
hogs  will  give  the  disease  to  susceptible  hogs  in  every  case.  Our 
knowledge  of  the  indirect  methods  of  transmission  has  come  from 
observation  of  outbreaks  of  cholera  and  by  correlating  this  disease 
with  other  infectious  diseases. 

It  is  generally  thought  that  the  virus  reaches  herds  in  the  follow- 
ing ways:  (1)  by  the  introduction  of  new  stock,  show  animals,  or 
stock  loaned  for  breeding  purposes;  (2)  by  the  transportation  of  hogs 
on  infected  cars  or  wagons  and  through  public  stock-yards  and  over 
highways;  (3)  by  dirt  from  insanitary,  cholera-infected  farms,  carried 
on  the  feet  of  men  and  animals  and  on  wagons  or  farm  implements; 
(4)  by  streams  and  irrigation  ditches;  (5)  by  animals  and  birds  that 
feed  upon  dead  hogs;  and  (6)  by  feeding  uncooked  pork  trimmings 
to  swine. 

Hogs  shipped  to  non-infected  territory  immediately  after  the 
serum  and  virus  treatment  may  spread  the  disease.      The  change  of 


3 

environment,  lack  of  care,  improper  feed  and  hygienic  conditions  inci- 
dent to  shipping  may  sufficiently  lower  the  vitality  of  the  animals 
with  the  result  that  some  of  the  hogs  break  with  cholera  and  serve 
to  scatter  infection  at  the  point  of  destination. 

Faulty  methods  of  vaccination  and  too  small  a  dose  of  serum  may 
result  in  heavy  losses  in  herds  treated.  Before  the  outbreak  is 
checked  cholera  may  have  spread  to  neighboring  herds  and  to  locali- 
ties previously  free  from  the  infection. 


GENERAL   PREVENTIVE    MEASURES 

To  prevent  cholera  from  spreading  and  to  keep  the  disease  out 
of  the  herd,  the  following  suggestions  are  offered: 

Keep  the  sick  hogs  isolated  and  confined. 

Locate  the  pens  and  feed  lots  so  that  the  hogs  will  not  have  access 
to  irrigation  ditches,  streams  and  public  highways. 

Provide  well-water  for  drinking. 

Isolate  new  stock,  returning  show  animals  and  returning  breeding 
stock,  for  at  least  two  weeks  and  disinfect  them  by  dipping  or  spray- 
ing before  quartering  with  other  hogs  on  the  premises.  The  time 
consumed  in  transportation  is  usually  short  and  cholera  does  not 
develop  until  several  days  after  the  arrival  of  the  hogs  on  the  farm. 
Also,  use  care  in  feeding  and  attending  the  quarantined  hogs  to 
prevent  carrying  the  infection  to  other  pens. 

Load  and  unload  all  susceptible  hogs  outside  of  public  stockyards 
and  ship  in  cleansed  and  disinfected  cars.  Hogs  may  be  given  the 
serum  alone  treatment  to  protect  during  shipment. 

Avoid  visiting  the  neighbor's  hog  pen  if  there  is  cholera  among 
his  hogs,  or  disinfect  the  shoes  before  leaving  the  infected  premises. 

Have  your  stock-buyer  disinfect  his  wagon  before  driving  into  your 
hog  lot. 

Keep  hog  pens  clean  and  sanitary  so  that  buzzards,  crows  and 
stray  dogs  will  not  be  attracted  to  them. 

Isolate  and  retain  for  later  shipment  all  recently  vaccinated  hogs 
until  two  weeks  after  treatment,  provided  that  all  are  free  from 
symptoms  of  cholera. 

Cook  before  feeding,  or  discontinue  feeding,  garbage  and  pork 
scraps  to  hogs  unless  they  are  immune  to  cholera.    Recent  experiments 


have  proved  that  fresh  refrigerated  pork  and,  in  many  cases,  salted 
and  smoked  hams  will  produce  cholera  if  fed  to  susceptible  pigs.  In 
the  early  stages  of  the  disease,  carcasses  of  hogs  show  no  lesions  and 
are  passed  for  meat  as  apparently  healthy.  The  cholera  virus  in  this 
meat  will  survive  refrigeration  and  the  curing  process  in  many  cases. 
Pork  trimmings  usually  go  into  the  garbage  can  uncooked  and  are 
often  fed  with  the  kitchen  scraps  to  hogs  that  are  unvaccinated.  It 
is  evident  that  an  outbreak  may  start  from  this  practice.  Full  grown 
city  garbage-fed  hogs  become  immune  to  cholera  as  the  result  of 
eating  pork  scraps.  Such  herds  are  continually  exposed  to  cholera 
infection  from  the  feed  and,  where  no  vaccination  is  employed,  the 
losses  in  weaned  pigs  often  amount  to  50  per  cent  before  immunity  is 
established. 


CONTROL    OF    OUTBREAKS    OF    HOG    CHOLERA    BY    DISINFECTION 

During  an  outbreak  of  hog  cholera  the  safety  of  the  neighbors' 
hogs  should  be  considered  equally  with  the  infected  herd.  Dis- 
infection and  clean-up  measures  to  destroy  the  virus  should  be 
immediately  employed  and  continued  until  all  evidences  of  cholera 
have  disappeared.  Hogs  showing  symptoms  of  disease  after  vaccina- 
tion should  be  confined  to  a  small  clean  pen  that  can  be  kept  clean 
and  can  be  completely  disinfected.  Dead  cholera  hogs  should  be 
cremated  or  buried  deeply  and  covered  with  quicklime.  Although  the 
entire  herd  may  be  immunized  to  resist  the  infection  on  the  premises 
every  effort  should  be  made  to  destroy  the  virus  as  a  protection  against 
a  recurrence  of  the  disease  in  the  herd  when  new  stock  is  admitted 
or  more  animals  added  by  birth  and  principally  to  safeguard  the 
neighbors'  herds. 

Disinfection  of  the  hog  lots  and  houses  depends  on  the  destruction 
of  the  cholera  virus  and  the  removal  and  exclusion  of  carriers.  Many 
old  wooden  buildings  with  decayed  floors  and  walls  cannot  be  com- 
pletely disinfected  and  may  harbor  the  virus  for  some  time.  Some- 
times because  of  poorly  constructed  houses  and  of  very  filthy  pens  it 
would  be  more  practical  to  remove  the  herd  to  new  quarters  on 
another  part  of  the  farm.  If  this  is  done  the  abandoned  houses  may 
be  removed  or  may  be  cleaned  thoroughly,  disinfected  and  left  exposed 
to  the  sun  and  natural  influences  for  several  months  to  rid  thorn  of 
infection.     The  hog  lots  may  be  freed  from  infection  by  placing  them 


under  cultivation  for  a  year.  The  first  step  to  completely  disinfect 
the  premises  consists  in  removing  all  manure,  litter  and  rubbish.  The 
manure  may  be  mixed  with  quicklime  and  used  for  fertilizer.  All 
litter  and  rubbish,  unsanitarj^  troughs,  rotten  boards  and  porous 
material  should  be  burned.  Filth  and  dirt  should  be  removed  from 
all  cracks  and  crevices  and  every  part  of  the  construction  material 
should  be  exposed  before  a  disinfectant  is  used.  The  cleansing  process 
is  just  as  important  as  the  disinfecting  process. 

A  disinfectant  solution  may  be  applied  with  a  large  brush,  but 
is  more  thorough  if  applied  with  a  force  pump  in  the  form  of  a  fine 
spray.  Enough  of  the  solution  should  be  used  to  thoroughly  soak 
the  part  covered.  The  ease  with  which  the  hog  houses  may  be  dis- 
infected depends  on  the  construction.  Cement  houses  are  readily 
cleaned  and  disinfected  while  rough  wooden  houses  require  more  of 
the  solution  and  preferably  more  than  one  application.  Pens  con- 
taining sick  hogs  should  be  sprayed  frequently,  especially  the  floors 
and  troughs.  After  disinfection  the  troughs  should  be  washed  out 
with  clean  water  before  they  are  used  for  feed. 

The  choice  of  a  disinfectant  against  hog  cholera  depends  on  its 
ability  to  kill  the  virus,  its  power  to  penetrate  construction  material 
and  its  cost.  A  very  satisfactory  disinfectant  is  compound  cresol 
solution  (XL'S.  P.),  used  in  the  proportion  of  one  part  of  concentrated 
solution  to  thirty  parts  of  soft  water.  Equally  efficient  substitutes 
are  any  of  the  coal  tar  disinfectants  that  are  guaranteed  to  contain 
50  per  cent  of  cresylic  acid.  The  latter  are  used  in  3  per  cent  solu- 
tion, made  by  adding  four  fluid  ounces  of  concentrated  disinfectant 
to  one  gallon  of  soft  water.  Other  substitutes  sometimes  used  are, 
lime,  chlorinated  lime,  carbolic  acid,  crude  carbolic  acid,  and  corrosive 
sublimate.  Lime  is  a  cheap  disinfectant  and  is  valuable  for  frequent 
spraying  of  walls,  ceilings  and  fences.  It  is  often  sprinkled  on  the 
floors  of  pens.  Chlorinated  lime  is  a  stronger  disinfectant  than  lime 
but  has  an  objectionable  odor.  Carbolic  acid  is  expensive  and  is 
not  effective  against  the  cholera  virus  in  3  to  5  per  cent  solution. 
Crude  carbolic  acid  varies  in  effectiveness  because  its  cresol  content 
varies.  Corrosive  sublimate  (mercuric  chloride)  is  one  of  the  strong- 
est disinfectants  in  the  proportion  of  one  ounce  to  eight  gallons  of 
water.  It  is  objectionable  because  it  is  poisonous  to  stock  and  it 
corrodes  metals. 


PREVENTION    BY    MEANS    OF   ANTI-HOG-CHOLERA   SERUM 

Should  hog  cholera  appear  in  the  herd,  the  only  means  of  protec- 
tion is  inoculating  with  anti-hog-cholera  serum  and  virus.  As  soon 
as  a  positive  diagnosis  of  cholera  has  been  made  the  herd  should  be 
treated.  Vaccination,  if  employed  before  the  disease  progresses,  will 
save  all  the  healthy  hogs  and  a  large  percentage  of  those  having  a  rise 
of  temperature.  It  will  not  save  the  visibly  sick  hogs.  Delay  in 
treatment  means  increased  losses  by  death  and  increased  cost  of  treat- 
ment because  more  serum  will  be  necessary,  and  it  also  multiplies 
infection,  making  it  harder  to  clean  up  and  control  the  spread  of  the 
disease  in  the  community. 

After  treatment  the  herd  should  be  kept  on  a  light  diet  and  given 
pure  drinking  water  for  a  period  of  two  weeks.  The  pens,  sleeping 
quarters  and  troughs  should  be  cleansed  daily  and  disinfected  im- 
mediately after  vaccination  and  twice  a  week  thereafter  until  all  signs 
of  cholera  have  disappeared.  Abscesses  and  blood  poison  may  develop 
after  vaccination  if  the  hogs  are  allowed  the  use  of  dirty  wallows  or 
mud  holes  and  filthy  pens.  All  dead  hogs  should  be  burned  or  buried 
deeply  and  covered  with  quicklime.  Hogs  which  develop  a  chronic 
form  of  the  disease  should  be  destroyed.  Most  of  them  would  die 
naturally  after  prolonged  suffering.  A  complete  recovery  is  very 
unusual  and,  as  a  rule,  recovered  hogs  are  not  worth  their  feed. 
Chronic  cases  are  chiefly  objectionable  because  they  keep  alive  the 
virus  of  cholera  on  the  premises  and  as  long  as  the  virus  is  present 
some  agent  may  pick  it  up  and  disseminate  it  about  the  neighborhood. 

ADDING    NEW    HOGS    TO    INFECTED    PREMISES 

The  virus  remaining  in  the  soil  on  an  infected  farm  may  be 
destroyed  by  natural  influences  in  a  short  time  or  it  may  remain 
virulent  for  months.  Conditions  of  soil  and  climate  vary  in  different 
parts  of  the  state  so  that  no  definite  time  required  to  destroy  infection 
can  be  set  to  apply  to  all  localities.  In  general  the  infection  remains 
a  shorter  time  in  summer  than  in  winter.  Experiments  have  shown 
that  the  virus  in  manure  and  filth  is  quickly  killed,  due  to  putrefaction 
and  fermentation  which  take  place  during  the  warm  part  of  the  year. 
During  the  cold  part  of  the  year  the  virus  will  live  longer  because 
putrefaction  is  slower.  The  virus  remaining  in  the  houses,  in  bedding 
and  troughs,  etc.,  can  be  destroyed  by  proper  disinfection. 


Restocking  with  non-vaccinated  animals  as  long  as  there  are  sick 
hogs  on  the  premises  is  unsafe.  Three  months  after  the  removal  of 
the  last  sick  hog,  provided  the  premises  have  been  completely  cleaned 
and  disinfected,  they  may  be  considered  safe  for  susceptible  hogs. 
Before  that  time  all  susceptible  stock  introduced  should  be  vaccinated. 


METHODS    OF    USING    ANTI-HOG-CHOLERA    SERUM 

There  are  two  methods  of  immunizing  hogs  against  cholera.  One 
method  consists  in  injecting  serum  alone,  the  other  in  injecting  virus 
(virulent  hog- cholera-producing  blood)  simultaneously  with  serum  in 
another  part  of  the  body.  Serum  alone  injected  into  a  susceptible 
hog  protects  against  cholera  for  a  period  of  three  to  six  weeks.  If 
this  hog  does  not  become  exposed  to  cholera  within  a  few  weeks 
following  the  serum  injection  the  immunity  conferred  by  the  serum 
gradually  lessens  and  the  hog  again  becomes  susceptible  to  cholera. 
Virus  blood  taken  from  a  hog  acutely  sick  with  hog  cholera  would 
kill  a  susceptible  hog  if  injected  alone,  but  will  not  if  a  dose  of  serum 
is  injected  simultaneously,  but,  on  the  other  hand,  will  confer  on  this 
hog  a  permanent  immunity.  In  small  pigs  the  immunity  is  sometimes 
outgrown  and,  therefore,  is  not  always  permanent. 


ADVICE    CONCERNING    VACCINATION 

Vaccination  is  not  advised  in  any  locality  unless  there  is  cholera 
present  in  the  herd,  or  it  is  exposed  to  the  infection.  General  vacci- 
nation of  all  hogs  would  be  a  needless  expense  and  might  spread 
cholera  in  localities  free  from  the  disease. 

In  infected  herds  the  temperatures  of  all  the  animals  should  be 
taken  to  ascertain  the  extent  of  infection  and  to  guide  in  the  dosage 
of  serum.  The  temperature  will  reveal  approximately  the  number 
of  hogs  that  have  cholera  and  will  give  some  idea  of  the  percentage 
of  losses  that  may  follow.  All  hogs  having  a  temperature  above 
104°  F.  should  be  regarded  as  infected  and  should  receive  at  least  a 
50  per  cent  increased  dosage  of  serum.  All  hogs  showing  visible 
cholera  symptoms  (staggers,  pneumonia,  paralysis,  sore  eyes)  should 
not  be  treated,  but  should  be  destroyed,  preferably  cremated. 

The  simultaneous  method  is  advised  in  sick  herds  on  all  hogs  except 
sows  about  to  farrow  and  pigs  less  than  three  weeks  old.     Results  in 


8 

the  field  have  shown  that  virus  given  to  hogs  with  a  temperature  due 
to  cholera  does  not  influence  the  course  of  the  disease  detrimentally 
and  that  recovery  is  just  as  frequent  as  with  serum  alone.  All  suck- 
ling pigs  cannot  be  permanently  immunized,  but  may  safely  be  given 
serum  alone,  or  serum  and  virus.  Sows  with  litters  may  receive 
serum  and  virus  provided  their  pigs  are  also  given  serum.  Pigs 
less  than  three  weeks  old  should  receive  serum  alone  and  should  be 
revaccinated  in  four  to  six  weeks  later  with  serum  and  virus.  As  a 
rule,  pigs  over  three  weeks  old  will  retain  their  immunity  until  they 
weigh  thirty  to  forty  pounds,  when  they  can  be  revaccinated  perma- 
nently with  serum  and  virus.  Sows  may  be  given  the  simultaneous 
treatment  safely  up  to  the  time  of  farrowing,  but  should  be  handled 
very  carefully  to  avoid  any  injury  that  may  result  in  abortion. 

In  herds  exposed  to  cholera,  but  not  infected,  the  temperatures  need 
not  be  taken  except  possibly  on  animals  that  are  in  poor  condition.  The 
simultaneous  method  is  advised  on  all  except  sows  about  to  farrow 
and  suckling  pigs  less  than  three  weeks  old.  The  latter  may  receive 
serum  alone  or  may  be  left  untreated  and  isolated  in  pens  removed 
from  possibility  of  infection  until  such  time  as  they  can  receive  serum 
and  virus.  The  optimum  time  to  treat  pigs  is  when  they  weigh  forty 
pounds  and  sows  before  they  are  bred  or  just  after  their  pigs  are 
weaned.  If  untreated  they  should  be  closely  watched  for  the  first 
signs  of  cholera. 

Pigs  from  immune  mothers  are,  as  a  rule,  immune  to  cholera  as 
long  as  they  are  nursed.  However,  they  may  become  infected  when 
a  few  weeks  old.  The  simultaneous  treatment  on  these  pigs  gives  a 
shorter  immunity  than  on  pigs  from  non-immune  sows. 

The  serum  alone  method  is  employed  where  an  immunity  of  only 
a  few  weeks  is  desired.  Animals  shipped  from  one  cholera-free  farm 
to  another  may  be  given  serum  alone  to  protect  them  from  fatal  ex- 
posure in  infected  cars  during  transportation.  This  method  is  also 
employed  on  animals  before  they  are  sent  to  shows  for  exhibition. 
Fat  hogs  ready  for  market  in  two  or  three  weeks,  if  exposed  to  infec- 
tion, should  receive  serum  alone. 

HOW  TO   VACCINATE 

The  day  before  treatment  all  hogs  should  be  segregated  according 
to  size,  confined  in  clean  pens,  given  plenty  of  water  and  light  feed. 
If  any  of  the  hogs  appear  sick,  separate  them  from  the  healthy  ones. 


to  gnJ^     1 

1    a  .  ■■  or 

EQUIPMENT    NECESSARY   TO    VACCINATE 


Figure  1  shows  the  equipment  necessary  to  vaccinate,  arranged  in  convenient 
form  ready  for  use.  The  numbers  indicate  the  following  articles:  (1)  A  white 
enamel  tray  holding  a  35  c.c.  and  a  45  c.c.  serum  syringe,  a  serum  filler,  a  cork- 
screw and  gauze  saturated  with  an  antiseptic  solution  to  cover  over  the  end  of 
syringes  when  not  in  use.  (2)  Two  clinical  thermometers  with  strings  attached. 
(3)  A  bottle  of  serum  with  cork  removed  and  a  filler  inserted.  (4)  A  small  white 
enamel  tray  holding  the  serum  needles.  (5)  Cotton.  (6)  A  bottle  of  compound 
cresol  solution.  (7)  A  metal  virus  syringe  case  holding  the  virus  needles.  (8) 
A  wide-mouthed  bottle  with  iodine  and  a  cotton  swab.  (9)  A  note  book  and 
pencil.  (10)  Towels.  (11)  A  white  enamel  tray  containing  two  6  c.c.  virus 
syringes  and  gauze  saturated  with  an  antiseptic  solution  for  covering  syringes. 
(12)   A  bottle  of  virus.       (13)    A  bucket  with  a  disinfecting  solution  and  brush. 

The  serum  needles  should  be  of  different  gauges  and  lengths.  For  injecting 
in  the  axillary  space  use  needles  of  16  gauge  and  1%  inches  long,  and  for  inject- 
ing in  the  neck  and  flank  use  needle  of  15  gauge  and  iy>  inches  long.  For  small 
pigs  needles  of  18  gauge  and  1  inch  long  are  the  best. 

The  virus  needles  should  all  be  of  18  gauge,  but  of  different  length.  Needles 
1  inch  and  1%  inches  long  are  the  most  desirable. 

The  serum  is  sometimes  poured  into  a  pint  fruit  jar  or  cup  with  a  cover  and 
drawn  directly  into  the  syringes.  This  method  admits  of  contamination  unless 
strict  precautions  are  taken.  A  better  method  would  be  to  perforate  the  cover 
of  the  jar  or  cup  and  insert  a  trochar  to  which  the  syringe  could  be  attached 
and  filled  without  the  serum  being  exposed  to  contamination.  Serum  may  also 
be  drawn  directly  from  the  bottle  if  two  needles  are  inserted  through  the  cork, 
one  needle  admitting  air,  while  the  serum  is  drawn  through  the  other. 


10 


The  animals  should  not  be  crowded  and  overheated,  nor  should 
they  be  vaccinated  during  the  hot  part  of  the  day  as  their  tempera- 
ture at  that  time  is  often  above  normal. 

The  table  or  box  holding  the  vaccinating  equipment  should  be 
placed  next  to  the  pen  where  the  work  is  to  be  done  and  may  be  cov- 
ered with  clean  newspapers  or  cheesecloth.  The  ground  about  it 
should  be  sprinkled  with  an  antiseptic  solution  to  prevent  dust. 

A  complete  vaccinating  equipment,  packed  in  a  small  grip,  may 
be  obtained  at  cost  price  from  the  Division  of  Veterinary  Science. 


Fig.  2. — Slioats  up  to  150  pounds  are  restrained  in  a  wooden  V-shaped 
trough  either  placed  on  the  ground  or  with  one  end  elevated.  The  needle  is 
inserted  through  the  skin  and  muscle  of  the  armpit,  well  back  from  the  shoulder 
and  inclined  away  from  the  ribs.  "When  the  needle  is  removed  there  should  be 
no  swelling  and  no  serum  should  leak  out.  To  avoid  nerves  inject  only  in  the 
posterior  two-thirds  of  the  armpit.  More  than  20  c.c.  of  serum  should  not  be 
injected  in  one  place  on  large  hogs. 


The  syringes,  needles,  fillers  and  glassware  used  should  be  sterilized 
by  boiling  in  water  for  five  minutes.  When  operating,  the  extra 
needles  should  be  kept  in  a  3  per  cent  compound  cresol  solution  (one 
tablespoonful  to  the  pint)  and  should  be  changed  for  each  animal. 
Keep  the  syringes  in  trays,  covered  with  gauze  saturated  in  a  strong 
antiseptic  solution.      The  serum  syringes  and  needles  should  be  kept 


11 


in  separate  trays  at  one  end  of  the  table  and  the  virus  syringes  and 
needles  in  trays  at  the  other  end  of  the  table. 

For  disinfecting  the  skin  around  the  point  of  injection,  3  per  cent 
compound  cresol  solution,  or  tincture  of  iodine  may  be  used.  If 
the  hogs  are  dirty  the  skin  should  first  be  washed  with  soap  and  water, 
dried  and  then  either  painted  with  iodine  or  washed  with  compound 
cresol  solution.-  Iodine  should  be  applied  to  the  dry  skin  and  is  to 
be  preferred  for  suckling  pigs  and  hogs  that  are  very  clean. 


Fig.  3. — Suckling  pigs  are  readily  vaccinated  when  held  by  the  front  legs, 
belly  forward  and  the  hind  legs  between  the  attendant 's  knees.  Serum  is  injected 
in  the  armpits  but  not  more  than  15  c.c.  should  be  injected  in  one  place.  Too 
large  a  dose  in  one  place  may  fail  to  become  absorbed  and  may  result  in  an 
abscess  forming.  In  small  pigs  a  few  drops  of  serum  or  virus  may  escape,  but 
this  can  be  prevented  by  pinching  the  skin  around  the  puncture  after  withdrawing 
the  needle.  It  is  a  good  practise  to  wipe  the  point  of  injection  with  a  cloth  rinsed 
in  some  disinfecting  solution. 


Plenty  of  help  should  be  secured  so  that  it  will  not  be  necessary 
for  the  operator  to  handle  the  hogs.  It  is  necessary,  if  the  work  is 
to  be  done  properly,  that  he  keep  his  hands  clean.  Three  men  can 
catch  and  hold  the  hogs  satisfactorily,  while  a  fourth  man  should  be 
provided  to  take  the  temperatures  and  do  the  washing.  The  operator 
does  the  injecting  and  filling  of  syringes  and  keeps  the  record,  which 


12 


should  contain  the  following :  The  kind  of  hog  (suckling  pig,  pregnant 
or  nursing  sow,  shoat,  boar,  etc.)  ;  temperature,  dose  of  serum  and 
virus,  remarks  (condition  of  animal,  breed,  number,  etc.). 

The  mouth  of  each  serum  bottle  should  be  washed  in  strong  dis- 
infectant solution  before  the  cork  is  removed  and  the  serum  filler 


Fig.  4. — Large  hogs  or  sows  heavy  with  pig  are  vaccinated  back  of  the  ear. 
They  may  be  restrained  in  a  chute  or  crate  or  snubbed  to  a  post  by  passing  the 
loop  end  of  a  rope  around  the  upper  jaw.  To  avoid  hitting  the  jowl  and  salivary 
gland  insert  the  needle  downward  and  backward  toward  the  shoulder. 


inserted.  Virus  can  be  drawn  directly  from  the  bottle  into  the  syringe 
without  removing  the  cork.  This  is  done  by  inserting  the  needle 
through  the  cork,  forcing  air  into  the  bottle,  and  then  withdrawing  the 
piston. 

It  docs  not  pay  to  inject  visibly  sick  hogs.  Anti-hog-cholera  serum 
is  a  preventive  and  not  a  cure.  In  the  early  stages  of  disease  a  large 
amount   of  serum  can   neutralize  the  virus  in  the  body  and  aid  the 


13 

animal's  recovery.  Some  of  the  visibly  siek  may  get  well  without 
serum.  In  such  cases  hygienic  treatment  does  more  good  than  serum. 
The  potency  of  virns  is' usually  destroyed  if  it  is  brought  in  contact 
with  antiseptics.  The  antiseptic  solution  in  the  needle  should,  there- 
fore, be  shaken  out  before  each  injection  is  made. 


DarTof  th7hnZ%t  ^w^  in1t°,  the  deep  muscles  of  the  ham  ■»*  i«  another 
pait  of  the  body  from  that  used  for  serum.  To  avoid  any  leakage  when  remnv 
mg  the  needle,  inject  with  the  skin  tightly  drawn  so  thatfwhen  Seised    it  Ti  1 

?ZriUL    %ne-edle  h°iein  ^  mUSClG-      The  Smallest  P^  should  receive \ot  les 
than  1  c.c.  of  virus  and  the  large  hog  not  less  than  2  c.c. 


All  virus  left  over  should  be  destroyed  by  heat  or  by  adding  to  it 
an  equal  volume  of  a  strong  antiseptic  solution. 

When  ordering  or  using  serum,  do  not  underestimate  the  weight 
of  the,  hogs.      Plenty  of  serum  should  be  used.      One  pig  saved  "by 


14 

the  liberal  use  of  serum  will  pay  for  the  increased  dosage  of  an  entire 
herd. 

Serum  and  virus  may  be  spoiled  by  heat  and  should  be  kept  away 
from  the  rays  of  the  sun  at  a  temperature  not  above  50  degrees. 
Where  possible  during  the  vaccination  of  a  herd  the  unopened  bottles 
of  serum  and  virus  should  be  kept  in  ice  water.  Metallic  cases  similar 
to  milk  sample  collecting  cases  with  a  central  ice  compartment  can 
easily  be  secured  for  this  purpose. 

After  treatment  the  hogs  should  be  given  a  light  feed  for  a  week 
and  should  be  kept  in  clean,  dry  quarters.  A  small  patch  of  alfalfa 
is  ideal.  Dirty  wallows  and  mud  holes,  streams  and  irrigation  ditches 
should  be  avoided.  In  cold  weather  avoid  exposure  to  cold  and 
dampness.  Hogs  readily  contract  pneumonia  and  pleurisy  after 
vaccination  and  bad  results  may  follow  the  neglect  of  proper  housing. 


HOW   TO    OBTAIN    SERUM    AND    VIRUS 

Serum  and  virus  should  always  be  ordered  from  a  laboratory 
holding  a  federal  or  state  license.  There  are  several  such  establish- 
ments in  this  state.  The  University  of  California  manufactures  anti- 
hog-cholera  serum  and  is  authorized  by  act  of  legislature  to  sell  it  at 
cost  of  production  to  any  bona-fide  resident  of  the  state  who  is  engaged 
in  hog  raising.  Virus  will  be  sent  for  use  only  by  a  qualified  man 
and  then  only  in  case  hog  cholera  exists  in  the  community,  but  excep- 
tion is  sometimes  made  to  this  rule  for  the  accommodation  of  breeders 
of  pure-bred  immune  swine.  The  present  cost  of  both  serum  and 
virus  is  l1/^  cents  per  cubic  centimeter.  All  serum  and  virus  sent 
out  by  the  University  of  California  is  made  under  the  supervision 
of  the  United  States  Bureau  of  Animal  Industry  Inspectors  and 
passes  all  federal  government  requirements  for  potency  and  purity. 

All  orders  will  be  shipped  C.CD.  unless  cash  accompanies  the 
order. 

Orders  may  be  sent  by  telephone,  telegraph  or  letter  and  are 
promptly  filled  and  shipped. 

All  communications  should  be  addressed  to  the  Veterinary  Divi- 
sion, University  of  California,  Berkeley,  California.  In  the  counties 
having  Farm  Advisors  the  serum  may  be  obtained  through  them. 


15 

In  order  to  estimate  the  amounts  of  serum  or  virus  needed,  when 
ordering,  refer  to  the  tables  given  in  the  following  facsimiles  of 
labels  used  by  the  University  of  California. 


ANTI-HOG-CHOLERA    SERUM 

FOR    THE    PREVENTION    OF    HOG    CHOLERA 

Before  using  the  serum,  read  the  directions  carefully.  Keep  the 
serum  in  a  cool,  dark  place,  preferably  near  ice.  Do  not  inject  visibly 
sick  hogs.     Increase  dosage  50$  for  hogs  having  a  high  temperature. 

U.    S.    VETERINARY    LICENSE    No.   78 


unt  250  C.C. 

after 

Serial  No 

Not  good 

Dosage: 

Weight  of  Hogs 

Amount  of  Serum 

50  pounds  or  less 

30  c.c. 

50  to    75  pounds    - 

'An  c.c. 

75  to  100  pounds 

- 

40  c.c. 

100  to  125  pounds    - 

45  c.c. 

125  to  150  pounds 

50  c.c. 

150  to  200  pounds    - 

60  c.c 

200  to  250  pounds 

70  c.c. 

Hogs  weighing  more   than    250    pounds.,    add   10  c.c 
for  each  50  pounds  weight,  maximum  90  c.c. 

Dose  thin  hogs  according  to  what  they  should  weigh  ii 

fair  flesh. 
Keep  at  an  even  temperature  from  40°  to  50°F. 

This  Serum  is  not  returnable. 

PREPARED    BY 

AGRICULTURAL    EXPERIMENT   STATION 

UNIVERSITY  OF   CALIFORNIA 

BERKELEY,    CALIFORNIA 


VIRULENT  H0G-CH0LERA  VIRUS 

II  AINU  E/K.— This  hlood  will  produce  hog-  cholera 
unless  anti-hog-cholera  serum  is  injected  at  the  same  time. 
Read  directions  carefully  before  using-.  Destroy  bottle  and 
any  remaining  contents  by  fire.  This  blood  cannot  be 
returned  for  credit. 

U.   S.   VETERINARY    LICENSE   No.   78 

Amount  50  C.C.  DOSAGE:         Serial  No 

Under  50  pounds      -        -        -        -        1      c  c. 

50  pounds  to  100  pounds    -        -         -     1%  c.c. 

100  pounds  to  300  pounds  -         2      c  c. 

Over  300  pounds    ...        -  3       c.c. 

AGRICULTURAL     EXPERIMENT    STATION 

UNIVERSITY  OF  CALIFORNIA,  BERKELEY 


STATION  PUBLICATIONS   AVAILABLE   FOR   FREE   DISTRIBUTION 


REPORTS 

1897.      Resistant  Vines,   their  Selection,   Adaptation,   and  Grafting.      Appendix  to  Viticultural 
Report  for  1896. 

1902.  Report  of  the  Agricultural  Experiment   Station  for   1898-1901. 

1903.  Report  of  the  Agricultural   Experiment   Station  for   1901-03. 

1904.  Twenty-second  Report  of  the  Agricultural  Experiment   Station  for    1903-04. 

1914.  Report  of  the  College  of  Agriculture  and  the  Agricultural  Experiment  Station, 

1913-June,   1914. 

1915.  Report  of  the  College  of  Agriculture  and  the  Agricultural   Experiment   Station 

1914-June,    1915. 

1916.  Report  of  the  College  of  Agriculture   and  the  Agricultural   Experiment   Station, 

1915-June,    1916. 

1917.  Report  of  the   College  of  Agriculture   and   the   Agricultural   Experiment    Station, 

1916-June,  1917. 

BULLETINS 


July, 
July. 
July. 
July, 


No.  No. 

230.   Enological  Investigations.  270. 

241.  Vine  Pruning  in  California,  Part  I. 

242.  Humus  in  California  Soils. 

246.    Vine  Pruning  in  California,  Part  II.  271. 

248.  The  Economic  Value  of   Pacific  Coast  272. 

Kelps.  273. 

249.  Stock-Poisoning  Plants  of  California. 

250.  The  Loquat.  274. 

251.  Utilization  of  the  Nitrogen  and  Organic 

Matter   in    Septic    and    Imhoff    Tank  275. 
Sludges. 

252.  Deterioration  of  Lumber.  276. 

253.  Irrigation   and   Soil   Conditions   in  the  277. 

Sierra  Nevada  Foothills,  California.  278. 

255.   The   Citricola    Scale.  279. 

257.   New  Dosage  Tables.  280. 

261.  Melaxuma    of    the    Walnut,     "Juglans 

regia."  281. 

262.  Citrus   Diseases   of   Florida   and   Cuba 

Compared  with  Those  of  California.  282. 

263.  Size  Grade  for  Ripe  Olives. 

264.  The  Calibration  of  the  Leakage  Meter.  283. 

265.  Cotton  Rot  of  Lemons  in  California.  284. 

266.  A  Spotting  of  Citrus  Fruits  Due  to  the  285. 

Action  of  Oil  Liberated  from  the  Rind.  286. 

267.  Experiments  with  Stocks  for  Citrus.  287. 

268.  Growing  and  Grafting  Olive  Seedlings. 

CIRCULARS 
No. 
152. 


A  Comparison  of  Annual  Cropping,  Bi- 
ennial Cropping,  and  Green  Manures 
on  the  Yield  of  Wheat. 

Feeding  Dairy  Calves  in  California. 

Commercial  Fertilizers. 

Preliminary  Report  on  Kearney  Vine- 
yard Experimental  Drain. 

The  Common  Honey  Bee  as  an  Agent 
in   Prune   Pollination. 

The  Cultivation  of  Belladonna  in  Cali- 
fornia. 

The  Pomegranate. 

Sudan  Grass. 

Grain   Sorghums. 

Irrigation  of  Rice  in   California. 

Irrigation  of  Alfalfa  in  the  Sacramento 
Valley. 

Control  of  the  Pocket  Gophers  in  Cali- 
fornia. 

Trials  with  California  Silage  Crops  for 
Dairy  Cows. 

The  Olive  Insects  of  California. 

Irrigation  of  Alfalfa  in  Imperial  Valley. 

The  Milch  Goat  in  California. 

Commercial  Fertilizers. 

Vinegar  from   Waste   Fruits. 


No. 
113. 
114. 
115. 
121. 

124. 
126. 
127. 
128. 
129. 
131. 
133. 
134. 
135. 
136. 
137. 
138. 
139. 


140. 


141, 

142. 

143. 

144. 
145. 

147. 
148. 
150. 
151. 


Correspondence  Courses  in  Agriculture. 

Increasing  the  Dutv  of  Water. 

Grafting  Vinifera  Vineyards. 

Some  Things  the  Prospective  Settler 
Should  Know. 

Alfalfa   Silage  for  Fattening  Steers. 

Spraying  for  the  Grape  Leaf  Hopper. 

House  Fumigation. 

Insecticide  Formulas. 

The  Control  of  Citrus  Insects. 

Spraying  for  Control  of  Walnut  Aphis. 

County  Farm  Adviser. 

Control  of  Raisin   Insects. 

Official  Tests  of  Dairy  Cows. 

Melilotus  Indica. 

Wood  Decay  in  Orchard  Trees 

The  Silo  in  California  Agriculture. 

The  Generation  of  Hvdrocvanic  Acid 
Gas  in  Fumigation  by  Portable  Ma- 
chines. 

The  Practical  Application  of  Irrmroved 
Methods  of  Fermentation  in  Califor- 
nia Wineries  during  1913  and  1914. 

Standard  Insecticides  and  Fungicides 
versus  Secret  Preparations. 

Practical  and  Inexpensive  Poultry  Ap- 
pliances. 

Control  of  Grasshoppers  in  Imperial 
Valley. 

Oidium  or  Powderv  Mildew  of  the  Vine. 

Su  erections  to  Poultrymen  concerning 
Chicken  Pox. 

Tomato  Growing  in  California. 

"Lnngworms." 

Round  Worms  in  Poultry. 

Feed  i ne  and  Management  of  Hogs. 


153 

154. 

155. 
156. 
157. 
158. 
160. 
161. 
162. 

164. 
165. 


166. 
167. 
168. 

169. 
170. 

171. 
17^. 

17^. 

1  74. 

175.' 

176. 

177. 
178. 


Some  Observations  on  the  Bulk  Hand- 
ling of  Grain  in  California. 

Announcement  of  the  California   State 
Dairy  Cow  Competition,    1916-18. 

Irrigation   Practice  in   Growing   Small 
Fruits  in  California. 

Bovine  Tuberculosis. 

How  to  Operate  an  Incubator. 

Control  of  the  Pear  Scab. 

Home  and  Farm  Canning. 

Lettuce    Growing   in    California. 

Potatoes  in   California. 

White    Diarrhoea    and    Coccidiosis    of 
Chicks. 

Small  Fruit  Culture  in  California. 

Fundamentals    of    Sugar    Beet    under 
California  Conditions. 

The  County  Farm  Bureau. 

Feeding  Stuffs  of  Minor  Importance. 

Spraying  for  the  Control  of  Wild  Morn- 
ing-Glory within  the  Fog  Belt. 

1918  Grain   Crop. 

Fertilizing  California  Soils  for  the  1918 
Crop. 

The  Fertilization  of  Citrus. 

Wheat  Culture. 

Th"    Construction    of    the    Wood-Hoop 
Silo. 

^irm   Dr^'nacre   Method^. 

Progress  Report  on  the  Marketing  and 

Distribution    of   Milk. 
ITo<r      Ch^Wa      Prevention      and      the 

Serum    Treatment. 
<^rnir>    Sovjrhum    Seed. 
The    Packing   of   Apples    in    California. 


